Among the many traits that made Charles Darwin one of the greatest minds in science was his pertinacious personality. Facing a daunting problem in natural history, Darwin would obstinately chip away at it until its secrets relented. His apt description for this disposition came from an 1867 Anthony Trollope novel in which one of the characters opined: "There ain't nowt a man can't bear if he'll only be dogged.... It's dogged as does it." Darwin's son Francis recalled his father's temperament: "Doggedness expresses his frame of mind almost better than perseverance. Perseverance seems hardly to express his almost fierce desire to force the truth to reveal itself."
Historian of science Frank J. Sulloway of the University of California, Berkeley, has highlighted Darwin's dogged genius in his own tenacious efforts to force the truth of how Darwin actually pieced together the theory of evolution. The iconic myth is that Darwin became an evolutionist in the Galápagos when he discovered natural selection operating on finch beaks and tortoise carapaces, each species uniquely adapted by food type or island ecology. The notion is ubiquitous, appearing in everything from biology textbooks to travel brochures, the latter inveigling potential travelers to visit the mecca of evolutionary theory and walk in the tracks of St. Darwin the Divine.
In June 2004 Sulloway and I did just that, spending a month retracing some of Darwin's fabled footsteps. Sulloway is one sagacious scientist, but I had no idea he was such an intrepid field explorer until we hit the lava on San Cristóbal to reconstruct the famous naturalist's explorations there. Doggedness is the watchword here: with a sweltering equatorial sun and almost no freshwater, it is not long before 70-pound water-loaded packs begin to buckle knees and strain backs. Add hours of daily bushwhacking through dry, dense, scratchy vegetation, and the romance of fieldwork quickly fades.
Yet the harder it got, the more resolute Sulloway became. He actually seemed to enjoy the misery, and this gave me a glimpse into Darwin's single-mindedness. At the end of one particularly grueling climb through a moonscapelike area Darwin called the "craterized district" of San Cristóbal, we collapsed in utter exhaustion, muscles quivering, and sweat pouring off our hands and faces. Darwin described a similar excursion as "a long walk."
Death permeates these islands. Animal carcasses are scattered hither and yon. The vegetation is coarse and scrappy. Dried and shriveled cacti trunks dot a bleak lava landscape so broken with razor-sharp edges that moving across it is glacially slow. Many people have died, from stranded sailors of centuries past to wanderlust-struck tourists of recent years. Within days I had a deep sense of isolation and of life's fragility. Without the protective blanket of civilization, none of us is far from death. With precious little water and even less edible foliage, organisms eke out a precarious living, their adaptations to this harsh environment selected for over millions of years. These critters are hanging on by the skin of their adaptive radiations. A lifelong observer of, and participant in, the creation-evolution controversy, I was struck by how clear the solution is in these islands: creation by intelligent design is absurd. Why, then, did Darwin depart the Galápagos a creationist?
Darwin ate his data on the voyage home.
The Darwin Galápagos legend is emblematic of a broader myth that science proceeds by select "eureka!" discoveries followed by sudden revolutionary revelations, whereupon old theories fall before new facts. Not quite. Paradigms power perceptions. Sulloway discovered that nine months after departing the Galápagos, Darwin made this entry in his ornithological catalogue about his mockingbird collection: "When I see these Islands in sight of each other, & possessed of but a scanty stock of animals, tenanted by these birds, but slightly differing in structure & filling the same place in Nature, I must suspect they are only varieties." That is, similar varieties of fixed kinds, rather than the myth that he already knew that evolution was responsible for the creation of separate species. Darwin was still a creationist! This quotation explains why Darwin did not even bother to record the island locations of the few finches he collected (and in some cases mislabeled) and why, as Sulloway has pointed out, these now famous "Darwin finches" were never specifically mentioned in On the Origin of Species.